Imaging new transient nanostructures using a microfluidic chip integrated with a controlled environment vitrification system for cryogenic transmission electron microscopy.
Nanostructures (vesicles, micelles, bilayers) are important in nanomedicine and biochemical processes. They are agents for encapsulation and eventual release of drugs, flavors, and fragrances. The structural transition from micelles to vesicles through disk-like intermediate states has been demonstrated previously. Here, we disclose a new route for the micelle-vesicle transition, where micelles aggregate to first form long tubules that become unstable, and break up into vesicles. A simple theory, based on energy principles, is presented to explain the tubule-vesicle transition. Observation of this new tubular intermediate state has been facilitated by the development of an integrated microfluidic chip/cryogenic transmission electron microscopy (cryo-TEM) unit. Although this transition has been observed in a specific amphiphilic system where micellar solutions of cetyltrimethylammonium bromide (CTAB) and dodecylbenzene sulfonic acid (HDBS) are mixed to form vesicles, this new tool can be applied broadly to study transient structures in nanoscale systems under the very controlled conditions provided by microfluidics.
Lee
Jinkee
J
Division of Engineering, Brown University, Providence, Rhode Island 02912, USA.
Jha
Ashish K
AK
Bose
Arijit
A
Tripathi
Anubhav
A
D001557:Benzenesulfonates / Q000032:analysis; D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry; D020285:Cryoelectron Microscopy / Q000295:instrumentation* / Q000379:methods; D004058:Diffusion; D004867:Equipment Design; D005898:Glass; D008051:Lipid Bilayers / Q000737:chemistry; D008823:Micelles; D044085:Microfluidics; D046529:Microscopy, Electron, Transmission / Q000295:instrumentation* / Q000379:methods; D049329:Nanostructures; D012984:Software; D013501:Surface-Active Agents
D001557:Benzenesulfonates; D002593:Cetrimonium Compounds; D008051:Lipid Bilayers; D008823:Micelles; D013501:Surface-Active Agents; C001114:dodecylbenzenesulfonic acid; D000077286:Cetrimonium